VRM4 - External and Internal Credit Ratings Flashcards
Define external rating scales, the rating process, and the link between ratings and default
External credit rating is attribute of an instrument, attributed by an entity
Lower rating means higher probability of default
Define conditional and unconditional default probabilities and explain the difference between the two
Unconditional is probability of default at time n. Conditional is probability of default at time n+1 given survival to n
Define and use the hazard rate to calculate the unconditional default probability of a credit asset
P default = 1 - exp(h*t)
Define recovery rate and calculate expected loss from a loan
Value of a bond shortly after default, % of face value
Expected loss = P default * (1 - recovery rate)
Explain and compare the through-the-cycle and point-in-time internal ratings approaches
Through the cycle tries to capture average credit worthiness of firm over years, point in time is best estimate of future default probabilities
Describe alternative methods to credit ratings produced by rating agencies
Alternative is to use a model produced by a bank or something, which can take into account a range of factors about a firm